TeXipedia

colonminus

Represents a colon followed by a minus sign as a single symbol, commonly used in mathematical logic and formal specifications.

Overview

Serves as a specialized notation primarily found in formal methods, computer science, and mathematical logic where precise symbolic representation is essential.

  • Frequently appears in formal specifications and proofs
  • Used to denote certain logical relations or definitions
  • Common in theoretical computer science notation
  • Helpful for expressing constraints or conditions in formal systems

Examples

Defining a function by removing elements from a set.

f:A={xX:xA}f \colonminus A = \{x \in X : x \notin A\}
f \colonminus A = \{x \in X : x \notin A\}

Expressing set difference using colonminus notation.

B:C={x:xBxC}B \colonminus C = \{x : x \in B \land x \notin C\}
B \colonminus C = \{x : x \in B \land x \notin C\}

Defining a restricted domain for a function.

f:D={(x,y)f:xD}f \colonminus D = \{(x,y) \in f : x \notin D\}
f \colonminus D = \{(x,y) \in f : x \notin D\}